With a panoramic view of the city skyline before them, residents living on top of Dayton's Bluff in the greater Eastside neighborhood of St. Paul, Minn., can see a new bridge take form to reconnect them to Lowertown and the downtown business and entertainment district.
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After a decade of tight lane restrictions and just months after crews demolished the former bridge to reduce it to tons of tangled rebar and concrete fragments, piers are in place and beam hoisting is under way on the new, Kellogg/Third Street Bridge.
The city of St. Paul awarded the $55 million contract to Lunda Construction of Rosemount, Minn. Lunda operates four offices across Minnesota and Wisconsin. SRF Consulting, with seven offices in the upper Midwest and one in Florida, serves as the engineer of record.
The reconstruction of the intersections with the Union Depot at the west end and Mounds Boulevard at the east end of the bridge are part of the contract package.
When announcing the start of construction of the bridge, Sean Kershaw, St. Paul Public Works Department director said, "This bridge is the longest city owned bridge and its construction is the largest and most complex infrastructure construction project in the city since 1995. We are thankful for the partnership of Lunda Construction, who are helping to bring a safer, more reliable connection to our city, regardless of whether you are driving, using public transit, walking or biking."
The land surrounding the bridge is deeply rooted in the history and culture of the Dakota tribes. This historic and rich cultural background with Minnesota's Indigenous population played a key role in the design and construction of the bridge.
Looking back through the last several hundred years, the tiny, 27-acre piece of land below the bridge and the bluffs above are sacred sanctuaries for the Dakota people.
According to the city of St. Paul website, the land below the bridge is home to the Wakan Tipi Cave (Dwelling Place of the Sacred) and a sacred shrine for the Indigenous people of this region.
Continuing from the city website, the land below the bridge became a busy railroad and industrial site where a section of the future corridor of I-94 would be constructed near the top of the bluff.
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To celebrate this cherished connection between the Dakota people and the city of St. Paul, native symbols and art will be featured on the new bridge.
Brent Christensen, assistant city bridge engineer, said the former bridge, built in 1980, replaced the old Third Street Viaduct, which was constructed in 1930.
"The city monitored the presence and progression of pier cap cracks on the 1980 bridge as part of the routine bridge inspection process," said Christensen. "SRF Consulting was hired to perform design services and performed a structural analysis of the bridge supports. Unexpectedly, SRF found that the pier cap cantilevers [which were properly designed to 1980 code] had less capacity than would be allowed by current design code. This unique case was due to changes in design code relating to how load paths transmit from beam through cap and into the column."
St. Paul Public Works staff immediately reduced the bridge deck from four to three lanes with one 6-ft. sidewalk and began the funding and engineering process to build a replacement bridge.
Securing funding to replace such a significant bridge was a decade-long effort, Christensen said. Meanwhile, city engineering and SRF staff drew up the design for a new bridge to be shovel-ready for construction.
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"The design and development of a Dakota cultural interpretive center ‘Wakan Tipi' ran concurrent with the bridge project. Saint Paul Public Works Department and SRF Consulting coordinated the bridge design and aesthetics with the Saint Paul Parks and Recreation Department and WTA.
"The Lakota concept of ‘kapemni' [representing twisting or mirroring of the earth and sky] influenced the hourglass aesthetic of the bridge piers. Additionally, local Native American artist Dyani White Hawk was commissioned to produce additional Dakota and Lakota art elements, which are cast into the concrete bridge piers nearest to the Wakan Tipi center," Christensen said.
When substantially complete in the late fall of 2026, the new crossing will carry traffic and pedestrians over I-94, a set of railroad tracks and the Wakan Tipi Nature Sanctuary.
The 2,100-ft. long, 13 span prestressed concrete bridge will carry four traffic lanes with 4-ft. shoulders. Anticipated and much improved additions to the bridge are two, 12-ft. wide pedestrian and bicycle lanes protected from traffic by concrete barriers. It will descend 90-ft. from the Dayton's Bluff neighborhood to the Lowertown community of downtown St. Paul.
When funding was finally secured in 2024 and with bridge plans in hand, Lunda crews mobilized and arrived on site in August 2024 to begin the demolition of the existing bridge.
Lunda crews rolled in a half dozen Cat and Volvo excavators and dozers for earth moving and demolition operations. For the lifting operations, Manitowoc and Terex cranes are on site, along with JLG and Genie man lifts.
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Quantities going into the new bridge include 17,500 cu. yds. of structural concrete; 1 mi. of ornamental railing; 57,000 ft. of 12-in. to 16-in. diameter steel pipe pile; and 16,000 ft. of 96-in.-tall MW shape prestressed beams.
With the safety of workers and visitors on the ground guiding their actions, dozens of iron workers and equipment operators began the rigorous removal of the bridge.
Working from east to west, crews rubblized the bridge deck operating two Cat 326s' attached with hydraulic breakers on the bridge deck.
"The beams were dropped to the ground as the bridge deck was removed. The beams were then processed on the ground using Cat and Volvo excavators attached with hydraulic breakers. The piers were tipped over and processed on the ground with the same equipment," said Jesten Sterry, Lunda vice president.
"The demo went well. The entire process took about seven months from late August 2024 through March 2025. The two spans over I-94 were removed in a weekend closure of the highway in December 2024. All the concrete debris and rebar were recycled.
"Over the railroads, the deck was saw-cut into 6-foot by 6-foot slabs and removed with excavators. The piers were saw cut into large pieces and removed with cranes. Whenever demolition above the tracks took place, we placed large wooden mats with steel plates over the tracks to protect them from the falling debris."
The Minnesota Department of Transportation (MnDOT) granted bridge crews a 36-hour time limit over that early December weekend to shut down I-94 to remove the span over the freeway.
"The removal went well," said Mike Reihl, Lunda senior project manager. "We were able to open the highway late Sunday night in plenty of time before the 5 a.m. deadline Monday morning."
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Existing storm sewers and the railroad tracks presented designers with a unique set of circumstances that led to an alternate design and construction at Pier 4.
"Pier 4 sits between the railroad tracks and two, 10-foot diameter storm sewer pipes. To meet railroad clearance requirements, Pier 4 was located very close to the storm sewers. At this location, the sewer and railroad tracks are skewed which necessitated skewing the pier to the alignment of the bridge.
"During the design process, the presence of the storm sewers was identified as a risk to the bridge's structural integrity if they were to break and potentially scouring out the bridge substructure.
"To mitigate this risk, the pier was designed for an ‘extreme event' condition, where the soil around the pier was ‘scoured' out, exposing the pile. This resulted in the need for a thicker walled pile at Pier 4 compared to the rest of the project," explained Jamison Beisswenger, SRF structures director.
Operating around the railroad tracks below and the beam delivery schedule required advanced planning and sometimes on-the-spot coordination between Lunda crews and the railroads.
The railroad hub below the east end of the bridge is one of the busiest railroad junction hubs in the upper Midwest, according to a city of St. Paul press release.
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The two freight railroads, BNSF and CPKC, remained active during construction, requiring Lunda crews to set the beams according to the railroads' schedule.
Coordination with railroad staff was done the morning of the set with the railroad flag person. After reviewing the daily train schedule, the flag person picked out a narrow, 1.5-hour window-of-time when there was no train traffic to set a beam, Reihl explained.
Transporting the beams into the work site required an approved and permitted route by the city and MnDOT through the streets of the city between 2 a.m. and 5 a.m.
"The beams were delivered two at a time. At 190 feet long, the beams spanning I-94 are the longest set of beams on the bridge. We set two beams on the day they were delivered or seven to eight beams a week," Reihl said.
By January, the last remaining set of beams to close the gap over I-94 had been delivered and were scheduled to be placed over a weekend that month.
However, cold weather and beam stability problems required rescheduling weekend road closures and beam installations. Two weeks into February, milder temperatures moved in and crews hoisted the final set of beams in place.
Bridge decking has started on the bridge and deck pours will begin in April. Lunda Construction is on schedule to open the bridge to traffic late in the fall of 2026. CEG
